Guys, you've broke completely my gaming experience!
Hud arrives all the time I click Alt (it is mapped in game to some command) and after returning there is huge framerate drop and I'm loosing 30 seconds to get back to game which is crucial in online multiplayer game.
Can this be disabled somehow? It was fine before this "fix".

Nazar, just use CCSM to disable the Hud keybinding or change it to something different (I use Super+space for example).

Unfortunately I don't think is possible to easily understand when the full-screen window is a game or something else (such as a browser, a video player or anything else that would benefit form this feature).

Maybe, you can somehow detect system load (I mean in terms of GPU or whether discrete graphics is enabled like in my case with built-in Intel and Nvidia in laptop through bumblebee).
Or even simpler (but narrow case) - I'm playing games from Steam, so when it is running - new behavior is not welcomed.

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Damn it!
Why are you all ignoring me? I'm suffering from this "Fix" every single time I'm launching fullscreen game!
Every click on "Alt" or "Super" causes multiple seconds of lost gameplay that is sometimes vital!
Are you seriously backported this ugly "feature" without any possibility to restore original behavior?
@azzar1 said he can add switch for this behavior, but there is no such option currently available.